1. Field of the Invention
The present invention relates to low voltage zone cabling through the use of a pre-terminated zone cables that provide all the advantages of traditional and existing zone cabling methods while minimizing or eliminating the disadvantages of traditional or existing zone cabling methods.
2. Description of Related Art
Since the early days of telephone systems, the cabling architecture used for premise building wiring was a zone type configuration. Before our modern cubical cities, buildings used an open floor and overlooking managerial office that was combined to allow managers to peer out and watch the staff work. The telephone was the first major communications device commonly distributed to the desktop. Because the facilities themselves hardly changed, cabling was installed using Telephone Terminal Cabinets (TTC's) which were tied back to a Main Distribution Frame (MDF) and associated key systems or patch facilities.
As common office communications grew to include fax machines and data lines (commonly used for computer dial up services), cabling that was once simplistic started to become more complex and difficult to manage. Furniture builders, no longer satisfied with providing desk units, began to produce cubical furniture for open office architecture that allowed for flexibility and a significant cost savings for space allocation. With the advent of Local Area Networks (LAN)/Wide Area Networks (WAN)-technology came deployment of newer cabling technology such as Category-3 (CAT-3), Coaxial (RF) Distribution, Category-5/5e (CAT-5/5e), and Fire-wire. The cabling used to reach from the MDF to the desktop became more and more important.
Communications infrastructure design has now essentially become an art form with as many as six different cables distributed to the desktop. Historically, most building designs, especially older buildings, such as schools and hospitals, did not provide adequate space for cable distribution. In recent years, it was thought that cables should be run directly from the MDF or equipment room to the desktop to reduce splicing and connection losses as cables are stressed to evolving faster network speeds. The Electronics Industry Alliance and Telecommunications Industry Association (EIA and TIA) began to address new requirements for campus premise cabling.
Due to ever-changing technology and the requirements of the cabling infrastructure, buildings now have more bulk weight from cables being run through their floors and ceilings than ever before. The lack of forethought given to cable distribution has made ceiling and floor plenum intertwined nightmares of cable infrastructure. This, compounded with a plethora of moves, additions, and changes (MAC's), has driven the cost of communications higher and higher.
Network cabling may be broken down into the following areas: main technology room (MTR); intermediate technology room (ITR); secondary ITR, zone cabling enclosures; backbone cabling; and station cabling.
The Main Technology Room (MTR) traditionally supports the file servers and implemented technologies. All backbone cables (copper and fiber) supporting voice and data technologies connect the MTR to multiple Intermediate Technology Rooms (ITR's). Occasionally, the MTR may support station cables (voice and data) installed within this room or returning to this room.
The intermediate technology room (ITR) traditionally supports star equipment technology (routers, hubs, and etc.), backbone cabling (copper and or fiber), station cabling, voice, and data, out to each workstation. Equipment and patch panels for data applications may be mounted onto racks. Voice equipment and voice applications traditionally may be mounted to the wall.
The consolidation point, secondary ITR, is where zone cabling solutions may be implemented, and consolidation points or secondary ITR may be incorporated into the design. Backbone cables (copper and fiber) may be installed in the ceiling riser shaft and connect the MTR to the ITR's. Data applications over copper wire generally have a total distance limitation of approximately 327 feet. This maximum distance includes the use of all patch cables. Typically all data applications on copper wire should be limited to a horizontal and vertical distance of 327 feet or 100 meters.
Voice applications over copper have fewer distance restrictions and can support distances of 2500 feet or greater. Fiber may be utilized for data application when distances exceed 100 meters. Fiber may be utilized for voice applications when the application requires it. Station workstation cables generally consist of at least one voice cable and at least one data cable.
In traditional cable installation, the station cable may be installed from the ITR or the MTR to each workstation location (furniture partition and or hard wall office), in a continuous run, i.e., without splices or breaks in the cable. The station cable may be pulled to length from 1000 feet cable spools, cut, and dressed to length. Each individual conductor may be terminated at the MTR or the ITR on a patch panel (data cable) or a station block (voice cable).
The station cable at the workstation side may either be dressed down a power pole and dressed into the wire management within the furniture partition or dressed up through a floor panel and into the wire management in the furniture partition. The station cables may be field terminated onto RJ45 female jacks and placed into a furniture partition faceplate.
Station locations in hard wall offices route the cable down the wall via pull string, conduit and box attached to the stud wall. Station cable conductors may be field terminated onto a RJ45 female jack or other generally recognized network connector with RJ45 being used as a representative only. The RJ45 female jack may then be placed into a faceplate and screwed into the conduit box.
A disadvantage of this cable installation method is that all cable must be installed as a home run (continuous from the ITR to the station location). When furniture partitions are moved, existing cables need to be cut from the RJ45 female jacks, pulled back into the ceiling before the furniture partitions can be broken down and reconfigured. Occasionally, existing cables may be re-worked and re-used. If existing cables cannot be re-used, these cables, by code, must be removed from the ceiling.
The majority of station cables typically are abandoned and must be removed. New station cables must be installed from the ITR to the new station locations. Sometimes these distances are 275 feet or greater. The cost a company incurs in the renovation may be at least threefold. First, there is the cost of labor to remove the abandoned cable. Second, there is the cost of wasting perfectly good cable that is just difficult to re-use. And third, there is the cost of labor and material to install new cable from the ITR to the new station location. Much of the cabling work must be completed after normal business hours, or on weekends, and paid at overtime rates, in an attempt to reduce employee down time resulting in delays and lost productivity in the work place.
When companies reconfigure their modular furniture, the cost to wire their facility is expensive because of the limited flexibility of moving or re-using existing home run cables.
Existing zone cabling solutions provide for an additional termination and patching point in the cabling solution. The previous zone approach allowed for remote patching in at least one of the two areas: raised floor and/or ceiling.
A zone cable solution, which utilizes a raised floor method, requires the client to install consolidation points, that is, distribution boxes strategically placed throughout the facility underneath the raised floor. The raised floor may be 4 to 6 inches in height. The raised floor may be installed throughout the majority of the office facility. Modular furniture and offices may be installed on top of the raised floor. Station cable may be installed in large quantities from the MTR and/or the ITR to the consolidation point box enclosures. The consolidation point box enclosures may be a termination point (extension of the MTR and ITR patch panels out to the floor). The consolidation points ordinarily remain permanently fixed. Station cable may be installed from these consolidation point box enclosures to workstations. In some cases, a long patch cable (RJ45 male to RJ45 male patch cable) may be installed from the consolidation point distribution box to the workstation to support voice and data devices.
An alternative to patch cord connection may be a cable extension to the workstation where the cable may be terminated at the workstation end onto a RJ45 female jack. Patch cables may be extended from this female jack to communications devices.
Raised floor panels may be opened to accommodate future MAC's (moves, additions, and changes) in the cabling infrastructure. If a reconfiguration in furniture is required, only the station cable or patch cord from the consolidation point distribution box to the workstation may be necessary to be moved or replaced. This results in a cost savings because the company is only replacing or reconfiguring the last 50 feet of cable instead of the total run of 250–300 feet of station cable.
A disadvantage of raised floor zone cable solutions is the cost to install raised floors throughout a company's facility. Few companies can justify the expense or return on investment unless they own their own facility.
Another disadvantage is that the installation of zone cable from the MTR and/or the ITR to the consolidation point distribution box may be accomplished by setting up multiple 1000-foot spools of 4 pair cable. The cables may be pulled to length, cut, dressed into the zone distribution box and then dressed into the ITR. The cables may be dressed back to freestanding racks and into the patch panels. Each cable may be dressed to the termination point at the back of the patch panel at both ends of the cable. The cable may be stripped back and the pairs carefully separated, placed onto the back of the patch panel and terminated. Each individual conductor must be properly placed, terminated, and tested.
The most time consuming part of a cable installation is separation, placement, and termination of cable. Utilization of a zone distribution alternative at least doubles the number of station cable terminations resulting in additional trouble points, increasing labor field costs, and increases the cost of materials, the number of zone distribution boxes, patch panels, and patch cords, along with the associated labor to install these items.
Additionally, raised flooring tile may be difficult to access for MAC work. It may require the removal of carpet tiles (which may overlay floor tiles), furniture, filing cabinets, and modular furniture may also need to be moved to gain access where required. Finally, raised floor tiles typically require the removal of at least 4 screws that hold each tile to the base.
Another disadvantage is that all terminations performed in the field are performed by numerous various installers, resulting in dissimilar connections, and leading to problems such as near end cross talk and signal impairment.
Ceiling zone distribution systems are configured and installed similar to a raised floor zone system. Multiple cable spools of 1000 feet may be set up and cable pulled to length, cut, and terminated in a ceiling consolidation point box enclosure. Station cable ports may be located throughout the ceiling and be available to support a given area within an office. The final fifty feet or so of station cable installation may be installed from the distribution panel to a workstation, down through a power pole, and into spaces provided in modular furniture, or up through a floor plenum and into the furniture partition. Once the cables are dressed into the furniture workstation, the cables may be terminated in each cubical onto an RJ45 female jack and tested.
The ceiling zone cabling solutions suffers some of the same disadvantages as the raised floor solution.
Another significant disadvantage of network cabling is that the cables come from the manufacturer without connective ends. Connective ends, such as the RJ45 connector are too large to fit through obstacles, conduits, face plates, and etc. and the release clip on a RJ45 male connector gets caught on obstacles causing damage to the RJ45 male connector.
There is a need for a sub-connector attached to cables at the factory. The sub-connectors need to be small enough to fit through common obstacles encountered during a network wiring installation. The sub-connectors should be adapted to operatively connect to a corresponding connector of the type commonly used in the wiring industry. The cables should be provided with a sub-connector at both ends thereof and when manufactured could be considered sub-patch connector cables, in contrast to patch cables provided with standard RJ45 connectors, such as those removed from buildings during MAC's. The sub-connectors should provide strain relief to prevent wires or fibers from becoming dislodged from the sub-connector during the cable installation process.
It can be seen that there is a need for a factory installed wiring guide, or wiring cage sub-connector attached to cable ends to permit proper positioning of conductors. The factory installed wiring guide needs to provide a quality termination and crimp to the cable that provides strain relief/support for the wires or fibers and the outer sheath of the cable.
It can be seen there is a need for a prefabricated cable provided with a wiring guide sub-connector having a size sufficient to fit into small cable conduits and modular furniture electrical openings. The wiring guide should be adapted to be insertable into a backside of an RJ45 female connector to complete termination of a station cable.
It can be seen there is a need for a prefabricated cable having a wiring guide connectable to an RJ45 female connector that permits the wiring guide of the cable to be inserted (installed) and removed (de-installed) a plurality of times into and out of an RJ45 connector. The wiring guide may be provided to connect a cable to either a male or female RJ45 connector.
It can be seen that there is a need for a zone cabling system that minimizes additional up front costs to install a network zone cabling system. It can also be seen that there is a need for a zone cabling system that eliminates field terminations and results in more consistent high quality connection/termination of jacks at the workstation, the consolidation point distribution panel, the main technology room and the intermediate technology room.
It can also be seen that there is a need for a zone cabling system that reduces labor cost to install zone cables with multiple setups on spools that are an exact length required from the main technology room or the intermediate technology room to the consolidation point distribution panel. It can also be seen that there is a need for a zone cabling system where no field termination is required and only the insertion of the wire guide and sub-connector combination into the back cavity of the RJ45 female connector is necessary.
It can also be seen that there is a need for a zone cabling system that provides flexibility to quickly reconfigure an office or modular furniture area. It can also be seen that there is a need for a zone cabling system that reduces labor costs labor future moves, additions and changes, (i.e. during original installation and labor cost for future) when only the last 25–75 feet of station cable has to be reconfigured.
It can also be seen that there is a need for a zone cabling system that reduces cost for materials because the station cable (sub-cable from consolidation point panel to workstation) can be used again and again. It can also be seen that there is a need for a zone cabling solution that provides marginal increased cost to make cable assemblies from lower cost labor pool versus offset by the higher labor cost savings in the field because of reduced installation and termination time.
It can also be seen that there is a need for a zone cabling system that provides manufacturer test results in the factory instead of or in addition to field testing, potentially resulting in time saved over mere field certification. The present invention fulfills these and other needs, and addresses other deficiencies of prior art implementations.